PETERS. — METABOLISM AND DIVISION IN PROTOZOA. 457 



Time 



No. of S ten tors . . 

 No. of Divisions . . 

 Mortality .... 

 IMean Result . 



A control experiment was made with a similar U-cell in which the 

 Stentors were treated merely with tap-water for twenty minutes, a period 

 of time equivalent to that of the test experiment. The animals were 

 then transferred, as before, to a portion of their native culture medium, 

 free from other Stentors, and mounted in hanging drops. These prepa- 

 rations were set away simultaneously with the test preparations and were 

 kept under the same room conditions. The only essential difference of 

 which I am aware between test and control experiments was the tem- 

 porary treatment of the former with 0.05 m. potassic chloride. The 

 control gave the following results : 



Time da. 1 da. 3 da. 



No. of Stentors . . 188 216 233 



No. of Divisions . . 48 



Mortality .... 4 



Mean Result ... 1.15 1.24 



Bxpt. No. 7, Oct. 24, 1901. 



Test experiment similar to Experiment No. 6. Culture medium made 

 to contain 0.05 m. potassic chloride applied to Stentors for ten minutes. 



Time .... 

 No. of Stentors 

 No. of Divisions 

 Mortality 

 Mean Result 



The control made as described under Experiment No. 6, yielded the 

 following results : 



Time .... 

 No. of Stentors 

 No. of Divisions 



Mortality . . 

 Mean Result 



